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Yayın A tunable inductance topology to realize frequency tunable matching networks and amplifiers(IEEE, 2013) Atilla, Doğu Çağdaş; Aydın, Çağatay; Köprü, Ramazan; Nesimoğlu, Tayfun; Yarman, Bekir Sıddık BinboğaCoverage of commercial communication standards such as GSM, UMTS, Wi-Fi and Wi-Max within a single transceiver chip is one of the most desired properties by wireless communication manufacturers. In this regard, communication companies are keenly interested in the design of high power amplifiers for broadband cellular communications to achieve this coverage. In this work, design of broadband tunable matching networks is investigated using Real Frequency Techniques. In practical applications, tunability is needed to compensate for the load impedance variations with environmental effects. In order to be able to work on sample structures, impedance transforming filters with proper topology are chosen and a broadband tunable matching network with a tunability strategy is developed. Eventually a broadband amplifier has been designed using the tunable inductor concept.Yayın Circuit model for given reflectance data constructed with mixed lumped and distributed elements for high speed/high frequency communication systems(IEEE, 2005) Yarman, Bekir Sıddık Binboğa; Şengül, Metin; Kılınç, Ali; Aksen, AhmetIn this paper, a reflectance-based "non linear interpolation method" is presented to model the measured or computed data, obtained from a "passive one-port physical device" using mixed lumped and distributed elements. Mixed element model is constructed with cascade connection of series inductors [L], commensurate transmission lines or so called Unit Elements [UE] and shunt capacitors[C]. Basis of the new model rests on the numerical generation of the scattering parameters of the lossless two-port constructed with cascade connection of simple [L]-[UE]-[C] elements which describes a lossless 2-port in Darlington sense. The new modeling technique does not require direct optimization of the circuit elements of the selected topology. Rather, two-variable reflection coefficient is directly determined by means of a non linear but "convergence guaranteed" interpolation process to best fit the given data. A low-pass filter input reflection coefficient modeling example is included to exhibit the utilization of the proposed modeling method.Yayın Single active device metamutator; Its application to impedance simulation and in particular to FDNR(IEEE, 2017) Minayi, Elham; Göknar, İzzet Cemhe proposed Metamutator configuration employs only one Fully Differential Current Conveyor (FDCCII) which has 9 terminals including ground. By properly interconnecting these terminals a 4-port Metamutator is obtained without use of any other external element. It maintains the following advantages: (i) use of only one active element: less is the number of active devices less is the amount of disparity, (ii) possibility of realizing Memristors, Capacitors, Inductors, Frequency Dependent Negative Resistor (FDNR), which can be used to make integrated circuit active filters, (iii) no need to impose component choice constraints. SPICE simulations' results using TSMC 0.18 mu m CMOS process parameters and +/- 0.9V supply voltages validate the theoretical predictions.Yayın CIM a current inverting metamutator and its application to universal filters among others(IEEE, 2017) Minayi, Elham; Göknar, İzzet CemA new kind of metamutator namely "Current Inverting Metamutator," its realizations using different types of active blocks and some of its applications are given in this paper. As a classical application of the metamutator simulation of a memristor and, as an original application, several schemes realizing universal filters are proposed. The post-layout characteristics of both applications, using TSMC 0.13 mu m process parameters with +/- 0.75 V power supply voltage, are presented to confirm the theoretical analysis.Yayın A frequency tunable broadband amplifier utilizing tunable capacitors and inductors(2013) Nesimoğlu, Tayfun; Aydın, Çağatay; Atilla, Doğu Çağdaş; Yarman, Bekir Sıddık BinboğaSoftware Defined Radio (SDR) technology aims employing commercial communication standards within a single transceiver unit. Therefore, the design of broadband frequency tunable microwave components; particularly tunable amplifiers have gained considerable importance in recent years. In this work, a tunable inductor topology is proposed, theoretically analyzed and simulated. By using tunable capacitors, tunable inductors were obtained and broadband tunable matching networks are designed. Eventually a frequency tunable broadband amplifier covering 800-7500 MHz band has been realized.Yayın MOS only oscillator using adder and subtractor circuits(IEEE, 2015) Yıldız, Merih; Göknar, İzzet Cem; Minaei, ShahramIn this paper an NMOS based sinusoidal oscillator is presented. The circuit is constructed with voltage-mode (VM) NMOS-based analog adder and subtractor circuits which respectively perform V-1+V-2 and V-1-V-2 operations on the input voltages. The most important feature of the proposed circuits is their extremely simple structures containing only twelve NMOS transistors (six for the adder, six for the subtractor). Another significant advantage of the proposed circuits is that no external passive components are being used. The post-layout simulations of the proposed oscillator circuit have been executed using TSMC 0.25 mu m process parameters with +/- 1.25 V power supply voltage.Yayın An active discharge scheme for DC-bus capacitors in EV powertrain(Institute of Electrical and Electronics Engineers Inc., 2025-07-18) Sezer, Mustafa Murat; Norwood, Daniel; Geiger, John; Hava, Ahmet Masum; Akın, BilalDuring the emergency situations, key-OFFs, or maintenance, discharging the inverter dc-bus capacitor voltage within seconds is imperative due to safety concerns (inverter not used to control motor). Conventional discharge methods rely on external resistors, additional switches, or motor windings, increasing cost, space requirements, and control complexity. This article presents a cost-effective and space-efficient solution that enables fast capacitor discharge by operating the inverter's SiC mosfets-either discrete devices or power modules-in linear mode. The proposed method utilizes a constant power tracking approach with pulse frequency modulation to safely discharge the high-voltage bus capacitor without external components. When the car is off, the proposed scheme discharges a 1000-V dc bus within 1 s using a single low-side SiC switch to test a worst-case scenario. In practice, all six devices can be used to share thermal stress, and the discharge time can be extended to 5 s as suggested by safety standards. Optimal operating conditions, including gate-source voltage (V{GS}) and pulse width (t{ON}}), are identified for different mosfets from various vendors. To assess long-term reliability, devices undergo more than 200 000 discharge cycles, with intrinsic parameter monitoring and failure analysis conducted to determine degradation mechanisms. The findings help establish safe operating conditions, ensuring robust and reliable integration of the proposed discharge method within the main powertrain inverter.Yayın Design of voltage-mode and current-mode PID controllers using a single Add-Differentiate IC (AD-IC)(Birkhauser, 2025-12-22) Minayi, Elham; Göknar, İzzet CemIn this paper, voltage and current mode proportional–integral–derivative (PID) controller circuits are presented in one topology, utilizing only a single active component, Add-Differentiate Integrated Circuit (AD-IC) along with two passive resistors and two passive capacitors. The effectiveness and performance of the proposed circuits are validated through sensitivity, non-ideality analyses and PSPICE and MatLab simulations.
